1,721,057 research outputs found
Tractive and soil compaction performances of an agricultural tractor fitted with rubber tracks
No full textThe objective of this study was to compare the tractive and the soil compaction performances of a conventional wheeled tractor with the fully tracked version of the same model.
The tested tractors were connected each other through a steel chain equipped with a load cell. The performances of the towing tractor were evaluated using the towed tractor as a brake, then the tractors were inverted in order to test both. The traction efficiency and the maximum draft force of the tractor were measured through the load cell and the tractor parameters acquired with a CAN logger. The soil compaction was evaluated through the analysis of soil bulk density and cone penetration test.
The results show a reduced soil compaction for the tracked tractor with respect to the wheeled version despite of the increase of the tractor mass due to the four rubber tracks weight. Furthermore, the tractor equipped with rubber tracks showed an improvement of the traction efficiency, especially on low grip surfaces
Performance evaluation of electrically driven agricultural implements powered by an external generator
Full text linkIn the last decade, many studies have been conducted on tractor and agricultural machinery electrification. In particular, the electrification of power take-off (PTO)-powered implements could support many benefits, such as improved comfort and safety during implement connection, less noisiness, accurate control of the implement rotational speed, and fuel consumption reduction. However, commercially available tractors do not generate sufficient electric power to run electrified implements. A solution to this issue is powering eventual electrified implements with an external electric generator powered by the PTO and mounted with the front three-point linkage. This study aimed to evaluate the potential benefits of using this combination with respect to PTO powered implements. The types of implements analyzed in detail in this study were a sprayer and a mulcher. Field tests were performed acquiring performance, operational, and environmental parameters. Results show that on the electrified implements, the absence of the cardan shaft and hydraulic remotes shortened the time required for the hitching phase and reduced the in-work noisiness. Field tests demonstrated that the electrified implements permitted an improvement of the fuel consumption per hectare, up to 33.3% and 29.8% lower than their PTO-powered homologue for the sprayer and the mulcher, respectively
Preliminary Study On Traction Efficiency Of An Agricultural Tractor Equipped With An Extendable Ballast Holder
No full textInfluence of Ploughshare Wear on Plough Efficiency
No full textRegarding agricultural machines, one of the main durability requirements are the wear resistance of the soil engaging tools. Wear of soil engaging tools should be minimized, since it impairs the tool specifications and affects tractor performances, tillage quality and machine maintenance costs. The purpose of this work was to investigate the impact of a worn ploughshare on tractor performances. Wear leads to a geometrical change of the soil engaging tools and previous studies investigated the relationship between the tool cutting edge geometry and the developed drought by means of trials and Finite Elements Modelling. However, no study has reported the influence of worn ploughshares on the power requirements of soil engaging tools. The methodology adopted in this study consists in a comparison of the tractor performances between its configuration with a plough equipped with a worn ploughshare and the configuration with the same plough with a new ploughshare. The tractor speed was measured with a GPS receiver and important tractor parameters such as engine torque and fuel consumption were acquired through a CAN logger
Feasibility study of an idling-stop device on agricultural tractors
No full textIdling is a vehicle condition in which the engine is running at the minimum rotational speed without accomplishing any useful work besides the generation of energy required to keep it rotating. Agricultural tractors may idle from 10 to 43% of their service time and this inoperative time must be minimized since it is deleterious for the environment, public health, and fuel economy. Idling could be reduced by adopting anti-idling devices such as the idling-stop. Despite it is well adopted on cars, it is not present on any commercial tractor. Since the engine restart requires an energy surplus from the battery to run the starter motor, idling-stop devices are not efficient for very short idling stops. This study aims to quantify the potential advantage of using an idling stop device. Engine startup tests were carried out to evaluate the electrical energy and the fuel used for the engine startup. The electrical energy was measured through an electrical current and voltage sensors placed on the battery poles. Results confirm that with very short idling periods an idling-stop device is not energy efficient since the power provided by the battery to run the starter motor is higher than the energy saved during the engine shutdown. The minimum idling time that permits energy savings is about 4 seconds
Special Issue: Engineering advances to improve the safety of agricultural machines
No full textAgriculture is one of the most hazardous of commercial sectors with every year many of its workers suffering occupational accidents and ill health. The International Labour Organisation (ILO) defines agriculture as the second greatest source of employment after services with more than a third of the world’s labour force. This Special Issue with the open call for papers aimed to demonstrate the importance of engineering advances in relation to the safety of agricultural machines with the main purpose of encouraging and investigating new research opportunities targeted improve human safety
An updated methodology to analyse the idling of agricultural tractors
Full text linkIdling is a status of tractors in which the engine is not subjected to any substantial load and the vehicle is stationary. Idling is detrimental for the environment and health of people and it is a frequent status for agricultural tractors. Indeed, agricultural tractors may idle from 10 to 43% of their entire operating time. Only in some conditions idling is necessary (e.g. implement hitching), otherwise it is a condition which wastes fuel. The aim of this paper is to report on an updated methodology to analyse the idling practice of agricultural tractors. Idling was monitored through a dash-cam and a CAN-Bus data logger installed on a tractor with a maximum engine power of 191 kW. The tractor ran on idle for 17% of its entire operating time with the most frequent stops occurring for the adjustment of the implement when the soil engaging tools become clogged by crop residuals. Moreover, during 67% of the idling duration, no tractor subsystem was used, so most of the idling was not caused by a real need. This idling was responsible for a waste of 1.6% of the fuel used. Considering that in Italy 8.3% of the tractors belong to the same class (in terms of mass) of that used in this study, 43 million of litres of fuel are supposed to be wasted per year. The results of this study could be used for developing anti-idling devices on agricultural tractors
Production and energy value of phragmites australis obtained from two constructed wetlands.
No full textCommon Reed (Phragmites australis (Cav.) Trin. ex Steud.), a perennial C3-grass, is the most commonly used plant species in constructed wetlands for wastewater treatment in Italy and is considered a potential biomass crop in Europe because it is high yielding and has low input requirements. Aboveground biomass for generating heat and power have been measured in two full-scale Horizontal Sub Surface Flow Constructed Wetlands (H-SSF CWs) case studies in Italy: a CW for tertiary treatment of piggery manure located in Veneto Region (N-Italy), and another for tertiary treatment of a municipal wastewater plant in Sicily (S-Italy). Both CWs were planted with Phragmites spp. at a density of 4 rhizomes/m2. Wastewater samples were analyzed for the evaluation of the chemical characteristics. The yield was measured at different harvesting times (early, mid and late winter). Dried plant samples were tested for the determination of the Higher Heating Value (HHV) and Lower Heating Value (LHV). Common Reed beds that are dense and homogeneous under Mediterranean climatic conditions are able to produce high annual biomass yield (approximately 105 t/ha). The aboveground biomass harvested in Catania has lower values of moisture (43.9%) compared to that in Padova (64.6%). This permits a higher LHV to be obtained during the combustion process
Production and energy transformation of herbaceous biomasses irrigated with treated wastewater - First results
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